The End of Diesel
Once upon a time, diesel fuel was going to be the future. It was seen as more efficient, on a mileage-per-gallon basis, than other fossil fuels, and for that reason was also thought to be less polluting. About two decades ago, acting on those beliefs, policy makers in Europe—where high energy prices already made mileage a more-pressing issue than in the U.S.—made a number of rules that incentivized the growth of diesel over gasoline for use in passenger cars, moving past its traditional role in trucking and construction. These policies were remarkably successful at meeting their goals, and diesel-powered cars soon accounted for half of the cars sold on the continent. Car companies poured resources into developing diesel-related technology. But the result of this success has been not greener, friendlier, cheaper motoring, but the creation of toxic clouds over major European cities. At the end of 2016, Paris was choked by its worst episode of smog in more than a decade, lasting longer than two weeks, according to the city’s pollution-watching agency Airparif, and prompting the city to enact emergency measures that included restricting car use. It was not the first time. During a March 2015 pollution event, Paris was briefly the most polluted city in the world, surpassing famously smoggy Beijing. London shared in the ignominy when it too beat out Beijing for the first time in January of this year.